Hello All,
Wanted to report that I ended up installing the Freezer 13 and replacing the lower end cpu cooler on the Z400. Very easy to install. Could not use the snap clips and pins from the box, but instead used the original screws from the original cooler. Once all was done, this system used to idle at around 38C with the AC ON. And under load it would go as high as 60C. With the AC off it would idle around 42 and and on load up to 66/67C which is not too bad to be honest.
with the Freezer 13, now it idles down to 28/29 with AC ON and around 35 with AC off. Under load it never goes beyond 54C either with AC ON or OFF. I am very impressed with this cooler.
I still plan on adding more intake fans on the case and create more postivive pressure to aid the GPU.
Will post pictures later!